Enhanced elevation detection for emergency response systems

ABSTRACT

At an emergency response system, a first location including a latitude and a longitude at which a first device is located is received. At an emergency response system, an air pressure reading measured by the first device is received. Using the air pressure reading and a mean sea-level barometric measurement, a first elevation of a device is computed. Using the first location, a corresponding street address is computed. Using the street address and the first elevation, a floor number is computed. The street address and the floor number are transmitted to a second device.

TECHNICAL FIELD

The present invention relates generally to a method, system, andcomputer program product for geolocation. More particularly, the presentinvention relates to a method, system, and computer program product forenhanced elevation detection for emergency response systems.

BACKGROUND

Emergency response systems—also known as 911 systems in the UnitedStates and Canada, but known by other numbers elsewhere—cannot only relyon the caller correctly relying the location of an emergency todispatchers. Callers may be lost, too incapacitated to provide addressdetails, too young to know such details, be outdoors in a locationwithout a definitive street address, or simply have forgotten in thestress of the emergency.

More modern emergency response systems (for example, Enhanced 911 orE911 in the United States and Canada) include the capability to send acaller's location to emergency dispatchers automatically. A databasematches calls from landlines with the known address of that landline.However, the database must be kept up to date to be effective. As well,large office telephone systems may only indicate one central location,even though there are many extensions that could be called from.

Cellular telephones do not have fixed addresses to store in a database.Instead, cellular telephones may be located by triangulating suchdevices using the cellular transmission towers they are within range of.For example, if a device is within the range of three transmissiontowers, the device must be within the intersection of the coverage areasof these three towers. However, triangulation is imprecise, particularlyin rural areas where towers are sparse and may have wide coverage areas.

More modern cellular telephones, such as smartphones, include componentsto report their location using satellite-based navigation systems suchas the Global Positioning System (GPS). However, GPS relies ontriangulation of signals from orbiting satellites, so is most accurateoutdoors, away from nearby buildings that attenuate or distort weak GPSsignals form the satellites.

Smartphones may also make calls using voice-over-Wi-Fi services, orsupplement GPS location capability using other available signals such asWi-Fi and Bluetooth. (Bluetooth is a registered trademark of BluetoothSIG, Inc.) However, such systems may also rely on databases that must bekept up to date and can improve precision only in areas where they areavailable. For example, one recent study found an overall locationaccuracy of about 120 meters, even with all available sensorscontributing.

In addition, all such location systems locate a caller based on thelatitude and longitude of the calling device, and cannot compute acaller's exact elevation. As a result, emergency responders often havedifficulty finding callers, particularly in large multi-flooredbuildings. For example, while a caller could summon help to atwenty-story office building, emergency responders would have much moredifficulty locating the correct floor and office suite within thebuilding.

SUMMARY

The illustrative embodiments provide a method, system, and computerprogram product. An embodiment includes a method that receives, at anemergency response system, a first location including a latitude and alongitude at which a first device is located. An embodiment receives, atan emergency response system, an air pressure reading measured by thefirst device. An embodiment computes, using the air pressure reading anda mean sea-level barometric measurement, a first elevation of a device.An embodiment computes, using the first location, a corresponding streetaddress. An embodiment computes, using the street address and the firstelevation, a floor number. An embodiment transmits, to a second device,the street address and the floor number. Thus, the embodiment provides amethod that computes a street address and floor number from a location,and transmits the street address and floor number to a second device.

Another embodiment includes a method wherein determining a correspondingstreet address includes comparing, using a processor and a memory, thefirst location against a database of known points of interest; andassociating, responsive to determining that the first location is withina pre-determined threshold of a point of interest in the database, thelocation with the street address of the point of interest. Thus, theembodiment provides a method that determines a street address using adatabase of known points of interest.

Another embodiment includes a method wherein determining a correspondingstreet address includes comparing, using a processor and a memory, thefirst location against a set of stored locations having correspondingstreet addresses; and associating, responsive to determining that thefirst location is within a pre-determined threshold of a second locationin the set of stored locations, the first location with the streetaddress of the second location. Thus, the embodiment provides a methodthat determines a street address using a set of stored locations.

Another embodiment includes a method wherein determining a correspondingstreet address includes comparing, using a processor and a memory, thefirst location against a database of known points of interest; andassociating, responsive to determining that the first location is withina pre-determined threshold of two points of interest in the databasehaving street addresses on the same street, the first location with astreet address comprising an interpolation between the street addressesof the two points of interest. Thus, the embodiment provides a methodthat determines a street address using a database of known points ofinterest.

Another embodiment includes a method wherein computing the floor numberincludes determining, from a database, a ground elevation correspondingto the street address; determining, from a database, a median floorheight corresponding to the street address; and computing the floornumber using the expression altitude−(Gh+Ah))/Eh, wherein altitudecomprises the first elevation, Gh comprises the ground elevation, Ehcomprises the median floor height, Ah comprise an average human waistheight, and a result of the expression is rounded to the nearest wholenumber. Thus, the embodiment provides a method that uses the streetaddress to compute the floor number.

Another embodiment includes a method that determines, from a databaseusing a processor and a memory, that the street address corresponds to abuilding having non-standard floor numbering. An embodiment determinesthat the floor number is affected by the non-standard floor numbering.An embodiment adjusts, responsive to the first and second determining,the floor number to compensate for the non-standard floor numbering.Thus, the embodiment provides a method that adjusts the floor number fornon-standard floor numbering.

Another embodiment includes a method that receives, at an emergencyresponse system, location information for a responder. An embodimentdetermines, using the street address, the first elevation, and the floornumber, a horizontal distance and a vertical distance to the location ofthe responder. An embodiment reports, to the first device, thehorizontal distance and the vertical distance. Thus, the embodimentprovides a method that reports a horizontal and vertical distancebetween a device and a responder's device.

Another embodiment includes a method that determines that the horizontaldistance is below a horizontal distance threshold and that the verticaldistance is below a vertical distance threshold. An embodiment reports,to the first device, a proximity alert. Thus, the embodiment provides amethod that reports a proximity alert when the horizontal and verticaldistance between a device and a responder's device is sufficientlysmall.

An embodiment includes a computer usable program product. The computerusable program product includes one or more computer-readable storagedevices, and program instructions stored on at least one of the one ormore storage devices.

An embodiment includes a computer system. The computer system includesone or more processors, one or more computer-readable memories, and oneor more computer-readable storage devices, and program instructionsstored on at least one of the one or more storage devices for executionby at least one of the one or more processors via at least one of theone or more memories.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain novel features believed characteristic of the invention are setforth in the appended claims. The invention itself, however, as well asa preferred mode of use, further objectives and advantages thereof, willbest be understood by reference to the following detailed description ofthe illustrative embodiments when read in conjunction with theaccompanying drawings, wherein:

FIG. 1 depicts a block diagram of a network of data processing systemsin which illustrative embodiments may be implemented;

FIG. 2 depicts a block diagram of a data processing system in whichillustrative embodiments may be implemented;

FIG. 3 depicts a block diagram showing hardware components of an exampledevice for enhanced elevation detection for emergency response systemsin accordance with an illustrative embodiment;

FIG. 4 depicts a block diagram of an example configuration for enhancedelevation detection for emergency response systems in accordance with anillustrative embodiment;

FIG. 5 depicts a flowchart of an example process for enhanced elevationdetection for emergency response systems in accordance with anillustrative embodiment;

FIG. 6 depicts a flowchart of a portion of an example process forenhanced elevation detection for emergency response systems inaccordance with an illustrative embodiment;

FIG. 7 depicts a flowchart of a portion of an example process forenhanced elevation detection for emergency response systems inaccordance with an illustrative embodiment;

FIG. 8 depicts a block diagram of another example configuration forenhanced elevation detection for emergency response systems inaccordance with an illustrative embodiment; and

FIG. 9 depicts a flowchart of an example process for enhanced elevationdetection for emergency response systems in accordance with anillustrative embodiment.

DETAILED DESCRIPTION

The illustrative embodiments recognize that the presently availabletools or solutions do not address these needs or provide adequatesolutions for these needs. The illustrative embodiments used to describethe invention generally address and solve the above-described problemsand other problems related to enhanced elevation detection for emergencyresponse systems.

An embodiment can be implemented as firmware or using a combination ofhardware and a software application. The application implementing anembodiment can be configured as a modification of an emergency responsesystem, as a separate application that operates in conjunction with anexisting emergency response system, a standalone application, or somecombination thereof.

Particularly, some illustrative embodiments provide a method by which adevice's elevation, as well as latitude and longitude, can be determinedand provided to an emergency response system, and a method by which anemergency response system can make use of the information.

An embodiment is capable of calling an emergency response system andcommunicating with the emergency response system using audio, audio andvideo, text, or any combination thereof. An embodiment is equipped tocall an emergency response system (such as 911 in the United States andCanada or a local equivalent elsewhere) over a landline or cellulartelephone network or using a voice-over-IP system. Another embodiment isequipped to exchange text messages, in any suitable format over anysuitable network, with an emergency response system equipped tocommunicate using text messages. Another embodiment is equipped toexchange video as well as audio with an appropriately-equipped emergencyresponse system. Another embodiment can exchange data, in any suitableformat over any suitable network, with an emergency response systemequipped to receive the data and forward the data toappropriately-equipped emergency responders.

An embodiment is capable of determining its location. For example, oneembodiment uses a satellite-based navigation system, such as GPS.Another embodiment supplements GPS location capability using otheravailable signals, such as Wi-Fi and Bluetooth. An embodiment determinesits location when a user initiates a call to an emergency responsesystem, or at any suitable earlier time.

An embodiment includes a barometer or other suitable air pressure sensorcapable of sensing atmospheric air pressure at the embodiment. To beginthe process of elevation determination, an embodiment takes an airpressure measurement. Alternatively, an embodiment takes a series ofmeasurements and computes a moving or weighted average of the series, tosmooth out noise and outlier measurements. For example, one embodimentuses a moving average of the last eight periodic measurements. Anembodiment determines its elevation when a user initiates a call to anemergency response system, or at any suitable earlier time.

Air pressure decreases, roughly exponentially, as elevation above areference point called mean sea level increases. Thus, air pressuremeasurements can be used to determine elevation. For example, theInternational Standard Atmosphere has a pressure reading of 29.92 inchesof mercury, or 1013.2 millibars or hectopascals, at sea level (0 feet or0 meters of elevation). In the lower atmosphere, for every 1000 feet(305 meters) of elevation increase, the pressure decreases approximately1 inch of mercury or 34 millibars. Thus, assuming a standard atmosphere,an air pressure reading at a location determines the elevation of thatsame location.

However, the real atmosphere is not standard. Instead, air pressurevaries with air temperature (cold air is typically denser than warm air)and as high- and low-pressure weather systems move through a location.To compensate, an embodiment must compute a correction. Weatherstations, such as those at airports, report mean sea-level barometricpressure, or the barometric pressure that would be measured at theweather station if the weather station was at sea level. For example, aweather station might report a mean sea-level barometric pressure of30.2 inches of mercury on a sunny winter day, and 29.1 inches of mercuryduring an intense summer rainstorm. Current (typically hourly) meansea-level barometric pressure for various locations are availablethrough many weather-related data sources.

Thus, an embodiment corrects its air pressure measurements against anearby mean sea-level barometric pressure measurement. If no measurementis within a pre-defined threshold distance, an embodiment corrects itsair pressure measurements against the average of several more distantmean sea-level barometric pressure measurements. Other methods ofobtaining a suitable mean sea-level barometric pressure measurement forcorrection purposes are also possible, and contemplated within the scopeof the illustrative embodiments. One correction method uses theexpression: altitude=c*(1.0−(Pma/P0){circumflex over ( )}t)+bias, wherealtitude denotes the altitude of the air pressure sensor corrected fornon-standard air pressure, Pma denotes an air pressure measurement, P0denotes a nearby mean sea-level barometric pressure measurement, and c,t, and bias are constants applicable to the particular barometric sensorof the embodiment. In this expression, altitude is in meters andpressure measurements are in Pascals. For example, in one embodiment,c=44330.77, t=0.1902632, and bias=0. If, after testing during animplementation phase of the embodiment, the expression results ininaccurate results when used at known altitudes using a variety ofpressure readings, any of bias, c, and t may be adjusted as necessary toobtain consistently correct results over an expected variety ofatmospheric conditions and known elevations.

An embodiment also determines its horizontal location, for example interms of latitude and longitude. An embodiment may use GPS for thispurpose, or GPS supplemented by another method, or any other suitablemethod.

From the determined location, an embodiment determines a correspondingstreet address. One embodiment compares the location against a databaseof known points of interest. If the location is within a pre-determinedthreshold of a point of interest in the database, the embodiment usesthe stored address of that point of interest. If no point of interest inthe database is close enough to the location, or if the database isunavailable, an embodiment determines whether registered locationinformation, for example from an app associated with the embodiment, isavailable and within a within a pre-determined threshold of thelocation. For example, a user may have previously associated the currentlocation with a location saved as “office”, with a corresponding streetaddress, in a navigation or weather app. If no match is within thethreshold using this method either, an embodiment reverse geocodes thelocation into a corresponding street address. Reverse geocoding convertsa location, in latitude and longitude, to an interpolated streetaddress. For example, if the location resolves to coordinates near themidpoint of a road segment that starts with address 1 and ends with 100,the interpolated street address will be somewhere near 50. Due to theinterpolation, reverse geocoding is not as accurate as the precedingmethods, so is only used if the other methods do not provide usefulinformation.

An embodiment uses the street address to determine if the caller isinside a building. If so, an embodiment uses the street address and thealtitude to determine which floor of the building the caller is on. Inparticular, an embodiment obtains the height of the ground at thelocation using publicly-available data. An embodiment also obtains anestimated median floor height for a region corresponding to thelocation. For instance, New York City skyscrapers may have a differentmedian floor height—perhaps 12 feet—than buildings in the Rochester,N.Y. suburbs—perhaps 10 feet—due to regional variations in buildingcodes, local preferences, or differences in construction methods betweentall city skyscrapers and lower-rise suburban buildings. An embodimentalso takes into account a typical human waist height, to account for anembodiment being held at waist level for pressure readings, then beingraised to head level for calling. In particular, an embodiment computesa floor number using the expression: floor=round((altitude−(Gh+Ah))/Eh),where floor denotes a floor number, altitude=the computed altitude ofthe embodiment, Gh=the ground height and Eh=the estimated median floorheight for the location, and Ah=an average human waist height. Here, theround( ) function rounds a parameter to the nearest whole number, andall units are in a suitable height unit, such as meters.

An embodiment also makes additional floor corrections, if appropriatedata is available for the location. For example, because some travelersconsider the number 13 unlucky, some hotels skip 13 when numberingfloors, and instead floor 14 is immediately above floor 12. If anembodiment determines a location in such a hotel, and the floorcalculation indicates the fifteenth floor (above the skipped floornumber, the embodiment adds one to the floor number to compensate.

Thus, when a user of an embodiment initially contacts an emergencyresponse system, the embodiment reports the user's location and, ifindoors, a calculated floor, to the emergency response system.

In addition, an embodiment continues to monitor pressure changes andre-compute the altitude for both the caller and a first responder alsoequipped with the embodiment. As a result, the embodiment determines theapproximate planar distance and altitude difference between the callerand the first responder. This determination assists the first responderin locating the caller, and indicates the closeness of help to thecaller.

One embodiment displays an indication of how high (or low) the caller isrelative to the first responder, to assist both parties in locating eachother. For example, an embodiment uses a scale of −10 to +10 to indicateproximity, with +10 denoting closest proximity and −10 denoting furthestaway. Other scales, and indicators such as floor numbers, distancemeasurements, and the number of floors separating the parties are alsopossible and contemplated within the scope of the illustrativeembodiments.

In one embodiment, when the weighted combination of the difference inlocation and altitude between the caller and the first responder fallsbelow a pre-defined threshold, the embodiment notifies the caller, thefirst responder, or both—thus alerting the caller that help is almostthere and letting the first responder know that the subject is nearby.Another embodiment includes several alert levels, at decreasingproximity thresholds.

The manner of enhanced elevation detection for emergency responsesystems described herein is unavailable in the presently availablemethods. A method of an embodiment described herein, when implemented toexecute on a device or data processing system, comprises substantialadvancement of the functionality of that device or data processingsystem in accurately determining height within a multi-story building toan emergency response system.

The illustrative embodiments are described with respect to certain typesof emergency response systems, communications, location sensing systems,sensors, corrections, databases, thresholds, validations, responses,measurements, devices, data processing systems, environments,components, and applications only as examples. Any specificmanifestations of these and other similar artifacts are not intended tobe limiting to the invention. Any suitable manifestation of these andother similar artifacts can be selected within the scope of theillustrative embodiments.

Furthermore, the illustrative embodiments may be implemented withrespect to any type of data, data source, or access to a data sourceover a data network. Any type of data storage device may provide thedata to an embodiment of the invention, either locally at a dataprocessing system or over a data network, within the scope of theinvention. Where an embodiment is described using a mobile device, anytype of data storage device suitable for use with the mobile device mayprovide the data to such embodiment, either locally at the mobile deviceor over a data network, within the scope of the illustrativeembodiments.

Another embodiment, implemented as part of an emergency response systemor as a standalone application operating in conjunction with anemergency response system, is capable of receiving calls to an emergencyresponse system and communicating with the calling device using audio,audio and video, text, or any combination thereof. The embodiment canexchange data, in any suitable format over any suitable network, with adevice calling an emergency response system. The embodiment is equippedto receive the data and forward the data to appropriately-equippedemergency responders.

When a suitably-equipped calling device initially contacts an emergencyresponse system, an embodiment receives reports of the calling device'slocation and, if indoors, a calculated floor number on which the deviceis located. In addition, an embodiment receives periodic updates of thecalling device's location and floor number. An embodiment also receivesperiodic updates of location and floor number for a first responder'sdevice, when the first responder's device is within a thresholdproximity of the calling device's location and floor number. Theembodiment relays the first responder's location and floor number to thecalling device, and relays the calling device's location and floornumber to the first responder's device, to assist the caller and firstresponder in locating each other.

Alternatively, an embodiment receives reports of the calling device'slocation and air pressure measurement, or reports of a first responder'sdevice's location and air pressure measurement, and computes acalculated floor number on which each device is located as well ashorizontal and vertical distances between the two devices.

The illustrative embodiments are described using specific code, designs,architectures, protocols, layouts, schematics, and tools only asexamples and are not limiting to the illustrative embodiments.Furthermore, the illustrative embodiments are described in someinstances using particular software, tools, and data processingenvironments only as an example for the clarity of the description. Theillustrative embodiments may be used in conjunction with othercomparable or similarly purposed structures, systems, applications, orarchitectures. For example, other comparable mobile devices, structures,systems, applications, or architectures therefor, may be used inconjunction with such embodiment of the invention within the scope ofthe invention. An illustrative embodiment may be implemented inhardware, software, or a combination thereof.

The examples in this disclosure are used only for the clarity of thedescription and are not limiting to the illustrative embodiments.Additional data, operations, actions, tasks, activities, andmanipulations will be conceivable from this disclosure and the same arecontemplated within the scope of the illustrative embodiments.

Any advantages listed herein are only examples and are not intended tobe limiting to the illustrative embodiments. Additional or differentadvantages may be realized by specific illustrative embodiments.Furthermore, a particular illustrative embodiment may have some, all, ornone of the advantages listed above.

With reference to the figures and in particular with reference to FIGS.1 and 2, these figures are example diagrams of data processingenvironments in which illustrative embodiments may be implemented. FIGS.1 and 2 are only examples and are not intended to assert or imply anylimitation with regard to the environments in which differentembodiments may be implemented. A particular implementation may makemany modifications to the depicted environments based on the followingdescription.

FIG. 1 depicts a block diagram of a network of data processing systemsin which illustrative embodiments may be implemented. Data processingenvironment 100 is a network of computers in which the illustrativeembodiments may be implemented. Data processing environment 100 includesnetwork 102. Network 102 is the medium used to provide communicationslinks between various devices and computers connected together withindata processing environment 100. Network 102 may include connections,such as wire, wireless communication links, or fiber optic cables.

Clients or servers are only example roles of certain data processingsystems connected to network 102 and are not intended to exclude otherconfigurations or roles for these data processing systems. Server 104and server 106 couple to network 102 along with storage unit 108.Software applications may execute on any computer in data processingenvironment 100. Clients 110, 112, and 114 are also coupled to network102. A data processing system, such as server 104 or 106, or client 110,112, or 114 may contain data and may have software applications orsoftware tools executing thereon.

Only as an example, and without implying any limitation to sucharchitecture, FIG. 1 depicts certain components that are usable in anexample implementation of an embodiment. For example, servers 104 and106, and clients 110, 112, 114, are depicted as servers and clients onlyas example and not to imply a limitation to a client-serverarchitecture. As another example, an embodiment can be distributedacross several data processing systems and a data network as shown,whereas another embodiment can be implemented on a single dataprocessing system within the scope of the illustrative embodiments. Dataprocessing systems 104, 106, 110, 112, and 114 also represent examplenodes in a cluster, partitions, and other configurations suitable forimplementing an embodiment.

Device 132 is an example of a device described herein. For example,device 132 can take the form of a smartphone, a tablet computer, alaptop computer, client 110 in a stationary or a portable form, awearable computing device, or any other suitable device capable ofcontacting an emergency response system. Any software applicationdescribed as executing in another data processing system in FIG. 1 canbe configured to execute in device 132 in a similar manner. Any data orinformation stored or produced in another data processing system in FIG.1 can be configured to be stored or produced in device 132 in a similarmanner.

Application 105 implements an embodiment described herein. Application105 runs on device 132. Application 105 implements another embodimentdescribed herein. Application 105 runs on any of servers 104 and 106,clients 110, 112, and 114, or any other suitable location connected tonetwork 102.

Servers 104 and 106, storage unit 108, and clients 110, 112, and 114,and device 132 may couple to network 102 using wired connections,wireless communication protocols, or other suitable data connectivity.Clients 110, 112, and 114 may be, for example, personal computers ornetwork computers.

In the depicted example, server 104 may provide data, such as bootfiles, operating system images, and applications to clients 110, 112,and 114. Clients 110, 112, and 114 may be clients to server 104 in thisexample. Clients 110, 112, 114, or some combination thereof, may includetheir own data, boot files, operating system images, and applications.Data processing environment 100 may include additional servers, clients,and other devices that are not shown.

In the depicted example, data processing environment 100 may be theInternet. Network 102 may represent a collection of networks andgateways that use the Transmission Control Protocol/Internet Protocol(TCP/IP) and other protocols to communicate with one another. At theheart of the Internet is a backbone of data communication links betweenmajor nodes or host computers, including thousands of commercial,governmental, educational, and other computer systems that route dataand messages. Of course, data processing environment 100 also may beimplemented as a number of different types of networks, such as forexample, an intranet, a local area network (LAN), or a wide area network(WAN). FIG. 1 is intended as an example, and not as an architecturallimitation for the different illustrative embodiments.

Among other uses, data processing environment 100 may be used forimplementing a client-server environment in which the illustrativeembodiments may be implemented. A client-server environment enablessoftware applications and data to be distributed across a network suchthat an application functions by using the interactivity between aclient data processing system and a server data processing system. Dataprocessing environment 100 may also employ a service orientedarchitecture where interoperable software components distributed acrossa network may be packaged together as coherent business applications.Data processing environment 100 may also take the form of a cloud, andemploy a cloud computing model of service delivery for enablingconvenient, on-demand network access to a shared pool of configurablecomputing resources (e.g. networks, network bandwidth, servers,processing, memory, storage, applications, virtual machines, andservices) that can be rapidly provisioned and released with minimalmanagement effort or interaction with a provider of the service.

With reference to FIG. 2, this figure depicts a block diagram of a dataprocessing system in which illustrative embodiments may be implemented.Data processing system 200 is an example of a computer, such as servers104 and 106, or clients 110, 112, and 114 in FIG. 1, or another type ofdevice in which computer usable program code or instructionsimplementing the processes may be located for the illustrativeembodiments.

Data processing system 200 is also representative of a data processingsystem or a configuration therein, such as data processing system 132 inFIG. 1 in which computer usable program code or instructionsimplementing the processes of the illustrative embodiments may belocated. Data processing system 200 is described as a computer only asan example, without being limited thereto. Implementations in the formof other devices, such as device 132 in FIG. 1, may modify dataprocessing system 200, such as by adding a touch interface, and eveneliminate certain depicted components from data processing system 200without departing from the general description of the operations andfunctions of data processing system 200 described herein.

In the depicted example, data processing system 200 employs a hubarchitecture including North Bridge and memory controller hub (NB/MCH)202 and South Bridge and input/output (I/O) controller hub (SB/ICH) 204.Processing unit 206, main memory 208, and graphics processor 210 arecoupled to North Bridge and memory controller hub (NB/MCH) 202.Processing unit 206 may contain one or more processors and may beimplemented using one or more heterogeneous processor systems.Processing unit 206 may be a multi-core processor. Graphics processor210 may be coupled to NB/MCH 202 through an accelerated graphics port(AGP) in certain implementations.

In the depicted example, local area network (LAN) adapter 212 is coupledto South Bridge and I/O controller hub (SB/ICH) 204. Audio adapter 216,keyboard and mouse adapter 220, modem 222, read only memory (ROM) 224,universal serial bus (USB) and other ports 232, and PCI/PCIe devices 234are coupled to South Bridge and I/O controller hub 204 through bus 238.Hard disk drive (HDD) or solid-state drive (SSD) 226 and CD-ROM 230 arecoupled to South Bridge and I/O controller hub 204 through bus 240.PCI/PCIe devices 234 may include, for example, Ethernet adapters, add-incards, and PC cards for notebook computers. PCI uses a card buscontroller, while PCIe does not. ROM 224 may be, for example, a flashbinary input/output system (BIOS). Hard disk drive 226 and CD-ROM 230may use, for example, an integrated drive electronics (IDE), serialadvanced technology attachment (SATA) interface, or variants such asexternal-SATA (eSATA) and micro-SATA (mSATA). A super I/O (SIO) device236 may be coupled to South Bridge and I/O controller hub (SB/ICH) 204through bus 238.

Memories, such as main memory 208, ROM 224, or flash memory (not shown),are some examples of computer usable storage devices. Hard disk drive orsolid state drive 226, CD-ROM 230, and other similarly usable devicesare some examples of computer usable storage devices including acomputer usable storage medium.

An operating system runs on processing unit 206. The operating systemcoordinates and provides control of various components within dataprocessing system 200 in FIG. 2. The operating system may be acommercially available operating system for any type of computingplatform, including but not limited to server systems, personalcomputers, and mobile devices. An object oriented or other type ofprogramming system may operate in conjunction with the operating systemand provide calls to the operating system from programs or applicationsexecuting on data processing system 200.

Instructions for the operating system, the object-oriented programmingsystem, and applications or programs, such as application 105 in FIG. 1,are located on storage devices, such as in the form of code 226A on harddisk drive 226, and may be loaded into at least one of one or morememories, such as main memory 208, for execution by processing unit 206.The processes of the illustrative embodiments may be performed byprocessing unit 206 using computer implemented instructions, which maybe located in a memory, such as, for example, main memory 208, read onlymemory 224, or in one or more peripheral devices.

Furthermore, in one case, code 226A may be downloaded over network 201Afrom remote system 201B, where similar code 201C is stored on a storagedevice 201D. in another case, code 226A may be downloaded over network201A to remote system 201B, where downloaded code 201C is stored on astorage device 201D.

The hardware in FIGS. 1-2 may vary depending on the implementation.Other internal hardware or peripheral devices, such as flash memory,equivalent non-volatile memory, or optical disk drives and the like, maybe used in addition to or in place of the hardware depicted in FIGS.1-2. In addition, the processes of the illustrative embodiments may beapplied to a multiprocessor data processing system.

In some illustrative examples, data processing system 200 may be apersonal digital assistant (PDA), which is generally configured withflash memory to provide non-volatile memory for storing operating systemfiles and/or user-generated data. A bus system may comprise one or morebuses, such as a system bus, an I/O bus, and a PCI bus. Of course, thebus system may be implemented using any type of communications fabric orarchitecture that provides for a transfer of data between differentcomponents or devices attached to the fabric or architecture.

A communications unit may include one or more devices used to transmitand receive data, such as a modem or a network adapter. A memory may be,for example, main memory 208 or a cache, such as the cache found inNorth Bridge and memory controller hub 202. A processing unit mayinclude one or more processors or CPUs.

The depicted examples in FIGS. 1-2 and above-described examples are notmeant to imply architectural limitations. For example, data processingsystem 200 also may be a tablet computer, laptop computer, or telephonedevice in addition to taking the form of a mobile or wearable device.

Where a computer or data processing system is described as a virtualmachine, a virtual device, or a virtual component, the virtual machine,virtual device, or the virtual component operates in the manner of dataprocessing system 200 using virtualized manifestation of some or allcomponents depicted in data processing system 200. For example, in avirtual machine, virtual device, or virtual component, processing unit206 is manifested as a virtualized instance of all or some number ofhardware processing units 206 available in a host data processingsystem, main memory 208 is manifested as a virtualized instance of allor some portion of main memory 208 that may be available in the hostdata processing system, and disk 226 is manifested as a virtualizedinstance of all or some portion of disk 226 that may be available in thehost data processing system. The host data processing system in suchcases is represented by data processing system 200.

With reference to FIG. 3, this figure depicts a block diagram showinghardware components of an example device 132 for enhanced elevationdetection for emergency response systems in accordance with anillustrative embodiment. Device 132 may be an end-user's device, used incalling an emergency response system for assistance, an emergencyresponder's device, or both. Device 132 is the same as device 132 inFIG. 1.

Device 132 includes display/touchscreen 310, which is suitable fordisplaying proximity indications when a first responder is nearby. As adisplay, component 310 is also suitable for displaying other device andcall status indications. For example, display 310 may display messagesor other indications that emergency services are being contacted, thatemergency services have answered the call, that emergency services areen route, and that the device's location, elevation, and floor have beendetermined. In addition, component 310 functions as a touchscreen,allowing the display of virtual keys a user can touch to input data,such as text or a telephone number, to device 132.

Device 132 includes calling components 320, which are capable of callingan emergency response system and communicating with the emergencyresponse system using audio, audio and video, text, or any combinationthereof. Device 132 also includes speaker 340 and microphone 350, foruse in communicating with an emergency response system.

Device 132 also includes location components 360, which are capable ofdetermining the location of device 132. Location components 360 usesGPS, a satellite-based navigation system. Location components 360supplement GPS location capability using other signals, such as Wi-Fiand Bluetooth, when available.

Device 132 also includes barometer 330 capable of sensing atmosphericair pressure at device 132. Device 132 also includes networkcommunications components 370. Components 370 allow device 132 tocommunicate over a data network, such as network 102 in FIG. 1, toobtain information. Such information includes mean sea-level barometricpressures for nearby locations, a database of known points of interest,registered location information, and the information required to performreverse geocoding. In addition, device 132 can communicate with anemergency response system using network communications components 370 inaddition to or instead of calling components 320.

With respect to FIG. 4, this figure depicts a block diagram of anexample configuration for enhanced elevation detection for emergencyresponse systems in accordance with an illustrative embodiment.Application 400 is an example of application 105 in FIG. 1, and runs indevice 132 in FIG. 1 or FIG. 3. Application 400 runs in an end-user'sdevice, used in calling an emergency response system for assistance, anemergency responder's device, or both.

Calling module 410 is responsible for calling an emergency responsesystem and communicating with the emergency response system using audio,audio and video, text, or any combination thereof. Calling module 410uses a landline or cellular telephone network, a data network such asnetwork 102 in FIG. 1, or any other suitable method supported byinstalled hardware and available connectivity.

Location module 420 is responsible for determining the location ofdevice 132, making use of GPS hardware and supplemented with othersignals, such as Wi-Fi and Bluetooth, when available. Elevation module430 determines the elevation of device 132, using local barometricpressure measurements corrected by mean sea-level barometric pressuremeasurements from nearby locations. Floor number module 440 converts theelevation measurement performed by elevation module 430 into a floornumber on which device 132 is situated, based on the height of theground at the location of device 132, the estimated median floor heightfor a region corresponding to the location, and a typical human waistheight. In particular, floor number module 440 computes a floor numberusing the expression: floor=round((altitude−(Gh+Ah))/Eh), where floordenotes a floor number, altitude=the computed altitude of theembodiment, Gh=the ground height and Eh=the estimated median floorheight for the location, Ah=an average human waist height, and theround( ) function rounds a parameter to the nearest whole number. Floornumber module 440 also makes additional floor corrections, ifappropriate data is available for the location of device 132.

In addition, proximity module 450 determines the approximate planardistance and altitude difference between a caller using device 132 and afirst responder responding to an emergency call. This determinationassists the first responder in locating the caller, and indicates thecloseness of help to the caller.

With reference to FIG. 5, this figure depicts a flowchart of an exampleprocess for enhanced elevation detection for emergency response systemsin accordance with an illustrative embodiment. Process 500 can beimplemented in application 400 in FIG. 4 and runs on device 132 in FIG.3. Process 500 runs in an end-user's device, used in calling anemergency response system for assistance, an emergency responder'sdevice, or both.

The process begins in block 502, in which a user contacts an emergencyresponse system. In block 504, the application determines the location,in latitude and longitude, of the caller's device. In block 506, theapplication determines the corrected elevation of the caller's device.In block 508, the application determines a street address correspondingto the location, in latitude and longitude, of the caller's device. Inblock 510, the application computes a floor number from the streetaddress and the corrected elevation of the caller's device. In block512, the application reports the street address and computed floornumber to the emergency response system. Finally, in block 514, theapplication reports on the proximity between the user and an emergencyresponder attempting to find the user.

With reference to FIG. 6, this figure depicts a flowchart of a portionof an example process for enhanced elevation detection for emergencyresponse systems in accordance with an illustrative embodiment. Process600 can be implemented in application 400 in FIG. 4 to run in anend-user's device, used in calling an emergency response system forassistance, an emergency responder's device, or both, such as device 132in FIG. 3, Process 600 can also be implemented in application 800 inFIG. 8 to run in a call-receiving application of an emergency responsesystem on servers 104 and 106, or clients 110, 112, and 114 in FIG. 1.Process 600 provides more detail regarding block 508 in FIG. 5 and block908 in FIG. 9.

The process begins in block 602, where the application determineswhether the device's location matches a point of interest in a point ofinterest database. If yes (“YES” path of block 602), in block 604 theapplication associates the device's location with the street address ofthe point of interest, then the application ends. If no (“NO” path ofblock 602), in block 606 the application determines whether the device'slocation matches an already-registered location. If yes (“YES” path ofblock 606), in block 608 the application associates the device'slocation with the street address of the already-registered location,then the application ends. Otherwise ((“NO” path of block 606), in block610 the application computes a street address corresponding to thedevice's location using reverse geocoding, then the application ends.

With reference to FIG. 7, this figure depicts a flowchart of a portionof an example process for enhanced elevation detection for emergencyresponse systems in accordance with an illustrative embodiment. Process700 can be implemented in application 400 in FIG. 4 to run in anend-user's device, used in calling an emergency response system forassistance, an emergency responder's device, or both, such as device 132in FIG. 3, Process 700 can also be implemented in application 800 inFIG. 8 to run in a call-receiving application of an emergency responsesystem on servers 104 and 106, or clients 110, 112, and 114 in FIG. 1.Process 700 provides more detail regarding block 510 in FIG. 5 and block910 in FIG. 9.

The application starts in block 702, where the application determines aground elevation corresponding to the already-computed street addressfor the device. In block 704, the application determines a median floorheight corresponding to the already-computed street address for thedevice. Then in block 706 the application computes a floor number fromthe ground elevation, median floor height, and an average human waistheight. Then the application ends.

With respect to FIG. 8, this figure depicts a block diagram of anotherexample configuration for enhanced elevation detection for emergencyresponse systems in accordance with an illustrative embodiment.Application 800 is an example of application 105 in FIG. 1, and runs inserver 104 in FIG. 1 in communication with device 132 in FIG. 1, or anyother suitable location.

Calling module 810, implemented as part of an emergency response system,is responsible for calling device 132 and communicating with device 132using audio, audio and video, text, or any combination thereof. Callingmodule 810 uses a landline or cellular telephone network, a data networksuch as network 102 in FIG. 1, or any other suitable method supported byinstalled hardware and available connectivity.

Call receiving module 815 is responsible for receiving calls from device132 to an emergency response system and communicating with device 132using audio, audio and video, text, or any combination thereof. Callingmodule 415 uses a landline or cellular telephone network, a data networksuch as network 102 in FIG. 1, or any other suitable method supported byinstalled hardware and available connectivity.

Location module 820 is responsible for receiving data for location ofdevice 132. Elevation module 830 determines the elevation of device 132,by receiving barometric pressure measurements from device 132, andcorrecting the barometric pressure measurements using mean sea-levelbarometric pressure measurements from nearby locations. Floor numbermodule 840 converts the elevation measurement performed by elevationmodule 830 into a floor number on which device 132 is situated, based onthe height of the ground at the location of device 132, the estimatedmedian floor height for a region corresponding to the location, and atypical human waist height. In particular, floor number module 840computes a floor number using the expression:floor=round((altitude−(Gh+Ah))/Eh), where floor denotes a floor number,altitude=the computed altitude of the embodiment, Gh=the ground heightand Eh=the estimated median floor height for the location, Ah=an averagehuman waist height, and the round( ) function rounds a parameter to thenearest whole number. Floor number module 840 also makes additionalfloor corrections, if appropriate data is available for the location ofdevice 132.

In addition, proximity module 850 determines the approximate planardistance and altitude difference between a caller using device 132 and afirst responder responding to an emergency call. This determinationassists the first responder in locating the caller, and indicates thecloseness of help to the caller.

With reference to FIG. 9, this figure depicts a flowchart of an exampleprocess for enhanced elevation detection for emergency response systemsin accordance with an illustrative embodiment. Process 900 can beimplemented in application 800 in FIG. 8 and runs in server 104 in FIG.1 in communication with device 132 in FIG. 1, or any other suitablelocation.

The process begins in block 902, an emergency response system receivescontact from a device, for example, device 132. In block 904, theapplication receives the location, in latitude and longitude, of thecaller's device. In block 905, the application determines whether thecaller's device is reporting a street address and floor number. If no(“NO” path of block 905, in block 907 the application determines whetherthe caller's device is reporting its elevation. If no (“NO” path ofblock 907, in block 916 the application reports lateral proximity, butnot horizontal proximity, between the user and an emergency responderattempting to find the user. If yes (“YES” path of block 907, in block906, the application determines the corrected elevation of the caller'sdevice. In block 908, the application determines a street addresscorresponding to the location, in latitude and longitude, of thecaller's device. In block 910, the application computes a floor numberfrom the street address and the corrected elevation of the caller'sdevice. Finally, in block 514 (also “YES” path of block 905), theapplication reports on the proximity between the user and an emergencyresponder attempting to find the user.

Thus, a computer implemented method, system or apparatus, and computerprogram product are provided in the illustrative embodiments forenhanced elevation detection for emergency response systems and otherrelated features, functions, or operations. Where an embodiment or aportion thereof is described with respect to a type of device, thecomputer implemented method, system or apparatus, the computer programproduct, or a portion thereof, are adapted or configured for use with asuitable and comparable manifestation of that type of device.

Where an embodiment is described as implemented in an application, thedelivery of the application in a Software as a Service (SaaS) model iscontemplated within the scope of the illustrative embodiments. In a SaaSmodel, the capability of the application implementing an embodiment isprovided to a user by executing the application in a cloudinfrastructure. The user can access the application using a variety ofclient devices through a thin client interface such as a web browser(e.g., web-based e-mail), or other light-weight client-applications. Theuser does not manage or control the underlying cloud infrastructureincluding the network, servers, operating systems, or the storage of thecloud infrastructure. In some cases, the user may not even manage orcontrol the capabilities of the SaaS application. In some other cases,the SaaS implementation of the application may permit a possibleexception of limited user-specific application configuration settings.

The present invention may be a system, a method, and/or a computerprogram product at any possible technical detail level of integration.The computer program product may include a computer readable storagemedium (or media) having computer readable program instructions thereonfor causing a processor to carry out aspects of the present invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, configuration data for integrated circuitry, oreither source code or object code written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Smalltalk, C++, or the like, and procedural programminglanguages, such as the “C” programming language or similar programminglanguages. The computer readable program instructions may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer or entirely on the remote computer or server. Inthe latter scenario, the remote computer may be connected to the user'scomputer through any type of network, including a local area network(LAN) or a wide area network (WAN), or the connection may be made to anexternal computer (for example, through the Internet using an InternetService Provider). In some embodiments, electronic circuitry including,for example, programmable logic circuitry, field-programmable gatearrays (FPGA), or programmable logic arrays (PLA) may execute thecomputer readable program instructions by utilizing state information ofthe computer readable program instructions to personalize the electroniccircuitry, in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the blocks may occur out of theorder noted in the Figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

What is claimed is:
 1. A method comprising: computing, at an emergencyresponse system, using an air pressure reading measured by a firstdevice and a mean sea-level barometric measurement, a first elevation ofthe first device; computing, a street address corresponding to a firstlocation of the first device; computing, using the street address andthe first elevation, a floor number; transmitting, to a second device,the street address and the floor number; determining, from a databaseusing a processor and a memory, that the street address corresponds to abuilding having non-standard floor numbering; determining that the floornumber is affected by the non-standard floor numbering; adjusting,responsive to the first and second determining, the floor number tocompensate for the non-standard floor numbering; receiving, at anemergency response system, location information for a responder;determining, using the street address, the first elevation, and thefloor number, a horizontal distance and a vertical distance to thelocation of the responder; and reporting, to the first device, thehorizontal distance and the vertical distance.
 2. The method of claim 1,wherein determining a corresponding street address further comprises:comparing, using a processor and a memory, the first location against adatabase of known points of interest; and associating, responsive todetermining that the first location is within a pre-determined thresholdof a point of interest in the database, the location with the streetaddress of the point of interest.
 3. The method of claim 1, whereindetermining a corresponding street address further comprises: comparing,using a processor and a memory, the first location against a set ofstored locations having corresponding street addresses; and associating,responsive to determining that the first location is within apre-determined threshold of a second location in the set of storedlocations, the first location with the street address of the secondlocation.
 4. The method of claim 1, wherein determining a correspondingstreet address further comprises: comparing, using a processor and amemory, the first location against a database of known points ofinterest; and associating, responsive to determining that the firstlocation is within a pre-determined threshold of two points of interestin the database having street addresses on the same street, the firstlocation with a street address comprising an interpolation between thestreet addresses of the two points of interest.
 5. The method of claim1, wherein computing the floor number further comprises: determining,from a database, a ground elevation corresponding to the street address;determining, from a database, a median floor height corresponding to thestreet address; and computing the floor number using the expressionaltitude−(Gh+Ah))/Eh, wherein altitude comprises the first elevation, Ghcomprises the ground elevation, Eh comprises the median floor height, Ahcomprise an average human waist height, and a result of the expressionis rounded to the nearest whole number.
 6. The method of claim 1,further comprising: determining that the horizontal distance is below ahorizontal distance threshold and that the vertical distance is below avertical distance threshold; and reporting, to the first device, aproximity alert.
 7. A computer usable program product comprising one ormore computer-readable storage devices, and program instructions storedon at least one of the one or more storage devices, the stored programinstructions comprising: program instructions to compute, at anemergency response system, using an air pressure reading measured by afirst device and a mean sea-level barometric measurement, a firstelevation of the first device; program instructions to compute, a streetaddress corresponding to a first location of the first device; programinstructions to compute, using the street address and the firstelevation, a floor number; program instructions to transmit, to a seconddevice, the street address and the floor number; program instructions todetermine, from a database using a processor and a memory, that thestreet address corresponds to a building having non-standard floornumbering; program instructions to determine that the floor number isaffected by the non-standard floor numbering; program instructions toadjust, responsive to the first and second determining, the floor numberto compensate for the non-standard floor numbering; program instructionsto receive, at an emergency response system, location information for aresponder; program instructions to determine, using the street address,the first elevation, and the floor number, a horizontal distance and avertical distance to the location of the responder; and programinstructions to report, to the first device, the horizontal distance andthe vertical distance.
 8. The computer usable program product of claim7, wherein determining a corresponding street address further comprises:program instructions to compare, using a processor and a memory, thefirst location against a database of known points of interest; andprogram instructions to associate, responsive to determining that thefirst location is within a pre-determined threshold of a point ofinterest in the database, the location with the street address of thepoint of interest.
 9. The computer usable program product of claim 7,wherein determining a corresponding street address further comprises:program instructions to compare, using a processor and a memory, thefirst location against a set of stored locations having correspondingstreet addresses; and program instructions to associate, responsive todetermining that the first location is within a pre-determined thresholdof a second location in the set of stored locations, the first locationwith the street address of the second location.
 10. The computer usableprogram product of claim 7, wherein determining a corresponding streetaddress further comprises: program instructions to compare, using aprocessor and a memory, the first location against a database of knownpoints of interest; and program instructions to associate, responsive todetermining that the first location is within a pre-determined thresholdof two points of interest in the database having street addresses on thesame street, the first location with a street address comprising aninterpolation between the street addresses of the two points ofinterest.
 11. The computer usable program product of claim 7, whereincomputing the floor number further comprises: program instructions todetermine, from a database, a ground elevation corresponding to thestreet address; program instructions to determine, from a database, amedian floor height corresponding to the street address; and programinstructions to compute the floor number using the expressionaltitude−(Gh+Ah))/Eh, wherein altitude comprises the first elevation, Ghcomprises the ground elevation, Eh comprises the median floor height, Ahcomprise an average human waist height, and a result of the expressionis rounded to the nearest whole number.
 12. The computer usable programproduct of claim 7, further comprising: program instructions todetermine that the horizontal distance is below a horizontal distancethreshold and that the vertical distance is below a vertical distancethreshold; and program instructions to report, to the first device, aproximity alert.
 13. The computer usable program product of claim 7,wherein the computer usable code is stored in a computer readablestorage device in a data processing system, and wherein the computerusable code is transferred over a network from a remote data processingsystem.
 14. The computer usable program product of claim 7, wherein thecomputer usable code is stored in a computer readable storage device ina server data processing system, and wherein the computer usable code isdownloaded over a network to a remote data processing system for use ina computer readable storage device associated with the remote dataprocessing system.
 15. A computer system comprising one or moreprocessors, one or more computer-readable memories, and one or morecomputer-readable storage devices, and program instructions stored on atleast one of the one or more storage devices for execution by at leastone of the one or more processors via at least one of the one or morememories, the stored program instructions comprising: programinstructions to compute, at an emergency response system, using an airpressure reading measured by a first device and a mean sea-levelbarometric measurement, a first elevation of the first device; programinstructions to compute, a street address corresponding to a firstlocation of the first device; program instructions to compute, using thestreet address and the first elevation, a floor number; programinstructions to transmit, to a second device, the street address and thefloor number; program instructions to determine, from a database using aprocessor and a memory, that the street address corresponds to abuilding having non-standard floor numbering; program instructions todetermine that the floor number is affected by the non-standard floornumbering; program instructions to adjust, responsive to the first andsecond determining, the floor number to compensate for the non-standardfloor numbering; program instructions to receive, at an emergencyresponse system, location information for a responder; programinstructions to determine, using the street address, the firstelevation, and the floor number, a horizontal distance and a verticaldistance to the location of the responder; and program instructions toreport, to the first device, the horizontal distance and the verticaldistance.
 16. The computer system of claim 15, wherein determining acorresponding street address further comprises: program instructions tocompare, using a processor and a memory, the first location against adatabase of known points of interest; and program instructions toassociate, responsive to determining that the first location is within apre-determined threshold of a point of interest in the database, thelocation with the street address of the point of interest.